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how much it was touched the farther from the poles; and that being touched in the circle drawn equidistant from the poles, answering the equinoctial of the world, it would have no respect at all. All which notwithstanding, many times musing with myself and think-ing on it, and finding as yet no other sufficient reason of the declination and variation both, I suppose it possible and likely that the loadstone generally and totally both may have such a respective force in it, as I have said, lying in his natural bed, or never taken out of it; and also may retain the same, and impart it forcibly enough, a good while after: if so be it be laid and kept still in the like situation. But the cause why few loadstones of many, do retain the same, [which made advertiss, in his first book Orbis Catorum, think there were divers kinds of them, some whereof he reports himself and others to have made sufficient trial, having more points of respect (namely, east and west) than others,] may be for that, for the most part without regard they are laid, or else by reason of their shape they fall and lie long in a diverse or contrary situation from that which was their natural: now that side upward which was downward, now that side eastward which was westward, now that side northward which was southward; whereby it comes to pass that within awhile, as they are much impaired in their two principal respective points of north and south, so they become, as it were, giddy and mopish, and at length almost quite defective in the other.

Now if this prove true, I dare avouch, that thereby is given a most certain and ready means of measuring the longitudes, or east and west distances; and withal a most easy way of sailing by a great circle, that is to say, the shortest cut, toward what position or situ-ation soever; the vertical touch for the most part being fittest for this use, and an equinoctial for the other, whereas the polar touch can demonstrate only the latitudes, although them of all other the most firmly. But touching these corollaries there needs not any further discourse, until experimental proof be made of the former problem.